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Derivatives. (Details) - Schedule of recognized gains (losses) for derivatives - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items] |  |
Realized Gains (Losses) | $ 2,102 | $ (4,568)
Unrealized Gains | 12,679 | 5,123
Non Designated Derivative Instruments [Member] | Cost of goods sold [Member] | Commodity Contracts [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Realized Gains (Losses) | 2,102 | (4,568)
Unrealized Gains | $ 12,678 | $ 5,123

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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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- Definition The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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